Le 14/12/2023 à 06:55, Nicholas Miehlbradt a écrit : > KMSAN expects functions __mem{set,cpy,move} so add aliases pointing to > the respective functions. > > Disable use of architecture specific memset{16,32,64} to ensure that > metadata is correctly updated and strn{cpy,cmp} and mem{chr,cmp} which > are implemented in assembly and therefore cannot be instrumented to > propagate/check metadata. > > Alias calls to mem{set,cpy,move} to __msan_mem{set,cpy,move} in > instrumented code to correctly propagate metadata. > > Signed-off-by: Nicholas Miehlbradt <nicho...@linux.ibm.com> > --- > arch/powerpc/include/asm/kmsan.h | 7 +++++++ > arch/powerpc/include/asm/string.h | 18 ++++++++++++++++-- > arch/powerpc/lib/Makefile | 2 ++ > arch/powerpc/lib/mem_64.S | 5 ++++- > arch/powerpc/lib/memcpy_64.S | 2 ++ > .../selftests/powerpc/copyloops/asm/kmsan.h | 0 > .../selftests/powerpc/copyloops/linux/export.h | 1 + > 7 files changed, 32 insertions(+), 3 deletions(-) > create mode 100644 tools/testing/selftests/powerpc/copyloops/asm/kmsan.h > > diff --git a/arch/powerpc/include/asm/kmsan.h > b/arch/powerpc/include/asm/kmsan.h > index bc84f6ff2ee9..fc59dc24e170 100644 > --- a/arch/powerpc/include/asm/kmsan.h > +++ b/arch/powerpc/include/asm/kmsan.h > @@ -7,6 +7,13 @@ > #ifndef _ASM_POWERPC_KMSAN_H > #define _ASM_POWERPC_KMSAN_H > > +#ifdef CONFIG_KMSAN > +#define EXPORT_SYMBOL_KMSAN(fn) SYM_FUNC_ALIAS(__##fn, fn) \ > + EXPORT_SYMBOL(__##fn) > +#else > +#define EXPORT_SYMBOL_KMSAN(fn) > +#endif > + > #ifndef __ASSEMBLY__ > #ifndef MODULE > > diff --git a/arch/powerpc/include/asm/string.h > b/arch/powerpc/include/asm/string.h > index 60ba22770f51..412626ce619b 100644 > --- a/arch/powerpc/include/asm/string.h > +++ b/arch/powerpc/include/asm/string.h > @@ -4,7 +4,7 @@ > > #ifdef __KERNEL__ > > -#ifndef CONFIG_KASAN > +#if !defined(CONFIG_KASAN) && !defined(CONFIG_KMSAN) > #define __HAVE_ARCH_STRNCPY > #define __HAVE_ARCH_STRNCMP > #define __HAVE_ARCH_MEMCHR > @@ -56,8 +56,22 @@ void *__memmove(void *to, const void *from, > __kernel_size_t n); > #endif /* CONFIG_CC_HAS_KASAN_MEMINTRINSIC_PREFIX */ > #endif /* CONFIG_KASAN */ > > +#ifdef CONFIG_KMSAN > + > +void *__memset(void *s, int c, __kernel_size_t count); > +void *__memcpy(void *to, const void *from, __kernel_size_t n); > +void *__memmove(void *to, const void *from, __kernel_size_t n); > +
The same is done for KASAN, can't you reuse it ? > +#ifdef __SANITIZE_MEMORY__ > +#include <linux/kmsan_string.h> > +#define memset __msan_memset > +#define memcpy __msan_memcpy > +#define memmove __msan_memmove > +#endif Will that work as you wish ? What about the calls to memset() or memcpy() emited directly by GCC ? > +#endif /* CONFIG_KMSAN */ > + > #ifdef CONFIG_PPC64 > -#ifndef CONFIG_KASAN > +#if !defined(CONFIG_KASAN) && !defined(CONFIG_KMSAN) > #define __HAVE_ARCH_MEMSET32 > #define __HAVE_ARCH_MEMSET64 > > diff --git a/arch/powerpc/lib/Makefile b/arch/powerpc/lib/Makefile > index 51ad0397c17a..fc3ea3eebbd6 100644 > --- a/arch/powerpc/lib/Makefile > +++ b/arch/powerpc/lib/Makefile > @@ -32,9 +32,11 @@ obj-y += code-patching.o feature-fixups.o pmem.o > obj-$(CONFIG_CODE_PATCHING_SELFTEST) += test-code-patching.o > > ifndef CONFIG_KASAN > +ifndef CONFIG_KMSAN > obj-y += string.o memcmp_$(BITS).o > obj-$(CONFIG_PPC32) += strlen_32.o > endif > +endif > > obj-$(CONFIG_PPC32) += div64.o copy_32.o crtsavres.o > > diff --git a/arch/powerpc/lib/mem_64.S b/arch/powerpc/lib/mem_64.S > index 6fd06cd20faa..a55f2fac49b3 100644 > --- a/arch/powerpc/lib/mem_64.S > +++ b/arch/powerpc/lib/mem_64.S > @@ -9,8 +9,9 @@ > #include <asm/errno.h> > #include <asm/ppc_asm.h> > #include <asm/kasan.h> > +#include <asm/kmsan.h> > > -#ifndef CONFIG_KASAN > +#if !defined(CONFIG_KASAN) && !defined(CONFIG_KMSAN) > _GLOBAL(__memset16) > rlwimi r4,r4,16,0,15 > /* fall through */ > @@ -96,6 +97,7 @@ _GLOBAL_KASAN(memset) > blr > EXPORT_SYMBOL(memset) > EXPORT_SYMBOL_KASAN(memset) > +EXPORT_SYMBOL_KMSAN(memset) > > _GLOBAL_TOC_KASAN(memmove) > cmplw 0,r3,r4 > @@ -140,3 +142,4 @@ _GLOBAL(backwards_memcpy) > b 1b > EXPORT_SYMBOL(memmove) > EXPORT_SYMBOL_KASAN(memmove) > +EXPORT_SYMBOL_KMSAN(memmove) > diff --git a/arch/powerpc/lib/memcpy_64.S b/arch/powerpc/lib/memcpy_64.S > index b5a67e20143f..1657861618cc 100644 > --- a/arch/powerpc/lib/memcpy_64.S > +++ b/arch/powerpc/lib/memcpy_64.S > @@ -8,6 +8,7 @@ > #include <asm/asm-compat.h> > #include <asm/feature-fixups.h> > #include <asm/kasan.h> > +#include <asm/kmsan.h> > > #ifndef SELFTEST_CASE > /* For big-endian, 0 == most CPUs, 1 == POWER6, 2 == Cell */ > @@ -228,3 +229,4 @@ END_FTR_SECTION_IFCLR(CPU_FTR_UNALIGNED_LD_STD) > #endif > EXPORT_SYMBOL(memcpy) > EXPORT_SYMBOL_KASAN(memcpy) > +EXPORT_SYMBOL_KMSAN(memcpy) > diff --git a/tools/testing/selftests/powerpc/copyloops/asm/kmsan.h > b/tools/testing/selftests/powerpc/copyloops/asm/kmsan.h > new file mode 100644 > index 000000000000..e69de29bb2d1 > diff --git a/tools/testing/selftests/powerpc/copyloops/linux/export.h > b/tools/testing/selftests/powerpc/copyloops/linux/export.h > index e6b80d5fbd14..6379624bbf9b 100644 > --- a/tools/testing/selftests/powerpc/copyloops/linux/export.h > +++ b/tools/testing/selftests/powerpc/copyloops/linux/export.h > @@ -2,3 +2,4 @@ > #define EXPORT_SYMBOL(x) > #define EXPORT_SYMBOL_GPL(x) > #define EXPORT_SYMBOL_KASAN(x) > +#define EXPORT_SYMBOL_KMSAN(x)